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Ground-level Ozone Pollution

Proposal to Revise the Regulatory Definition of Volatile Organic Compounds – Exclusion of cis-1,1,1,4,4,4-hexafluorobut-2-ene (HFO-1336mzz-Z)

April 23, 2018 - EPA is proposing to add HFO-1336mzz-Z to the list of compounds excluded from the regulatory definition of volatile organic compounds or VOC. Some VOC contribute significantly to the formation of ground-level ozone which can cause serious respiratory illnesses.

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